Liquid filter



March 11, 1952 A. GUIOT LIQUID FILTER Filed March 14, 1949 2 SHEETS-SHEET l r INVENTOR.

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Patented Mar. 11, 1952 LIQUID FILTER Auguste Guiot, Paris, France, assignor to Fram Corporation, a corporation of Rhode Island Application March 14, 1949, Serial No. 81,353 In France April 23, 1948 3 Claims. (cram-164) It is known that filters used for filtering combustibles such as fuel oil, intended for feeding motors, burners or similar installations, entail frequent cleaning and especially the replacement of the inside filtering cartridge. But the opening of the filter for cleaning and the replacement of the cartridge inevitably let the air in the delivery pipe which causes considerable trouble when starting again to feed the equipment.

The filter covered by the invention intends to eliminate entirely this difficulty. To this effect, it comprises, in the head of said filter, a small auxiliary vat or chamber which, during the draining and the taking apart of the filter, remains always filled with liquid, thus forming a hydraulic seal which prevents the entrance of air into the delivery pipeline. An air drain plug is also provided at the top of the filter head to allow the draining of the air upon the entrance of liquid after draining. A liquid filling plug is also provided in the upper wall of the head to enable the filling in advance of the pipe line supply to full capacity, and in conjunction with the draining plug, enables the complete draining of the air driven by the rise of the liquid.

This system permits the filter to be drained and the inside cartridge to be changed without at any time allowing the entrance of air into the delivery pipeline.

The attached drawings give an example of a method of embodiment of the filter which is the object of this invention.

Fig. 1 of these drawings is a vertical and longitudinal section of the filter;

Fig. 2 is a plan view.

As shown by the drawings, the filter comprises a head a, fastened permanently by means of side tongue al and including an inlet nozzle 1), connected to the feed line of the liquid combustible bl, and an outlet nozzle connected with the outlet pipeline of the combustible cl.

Under the head a is a removable container (1 which is a, part of the filter, in which is placed the filtering cartridge e. A hollow rod in is provided with side openings hi and is screwed into head a or into a connecting means 2', fastened in said head. This construction allows the cartridge e to be tightened between two compressible gaskets y and to be maintained in position in the container, the spring is insuring the fiexibility of the tightening.

In the head a of the filter is provided a chamber extending from the delivery pipe 0 and sealed at its base by a plug g; this chamber 1, which forms a stationary auxiliary compart- 2 ment, fills with liquid combustible up to level NN.

When container d is separated from head a, this auxiliary compartment maintains its liquid protection which forms thus a hydraulic seal protecting the outlet pipeline 0-0! against the entrance of air.

At the top of the head a of the filter is a drain plug I, which is threaded and' is provided with a small peripheral channel Z which, when the plug is slightly loosened, allows the outlet of the air contained in the upper part of the filter. Another plug m, also threaded, provided in the upper wall of the head a allows the filling oi the filter after the latter has been re-assembled.

On head a is also provided advantageously another pipe n (Fig. 2) including a spring valve 0 forming by-pass, which allows the liquid to return to the tank when the feed is shut ofi.

Container d comprises also at its base, in the usual manner, a removable plug p allowing the draining of the filter.

The operation of the filter arranged in the above manner is as follows:

In normal operation, the oil or other liquid combustible, coming in through pipe b-bl fills the filter, and according to the direction indicated by arrows, goes through the cartridge e and passed through openings hl in the hollow of the center rod h, and from there, enters the auxiliary chamber j to go out by the delivery pipe c-cl.

When the filter is to be disassembled for the replacement or the cleaning of the filtering cartridge e, the filter is previously emptied by unscrewing the lower drain plug 10, then the center rod 71. is unscrewed to liberate container a and the filtering cartridge e. During this operation, a certain amount of liquid combustible stabilizes itself in the auxiliary compartment 1 which remains filled up to level NN, and therefore, there is created automatically ahead of the outlet pipeline c-cl a hydraulic seal which protects this pipeline against any introduction of air.

For the assembling of the filter, the container d is put back into place with a new or cleaned cartridge e, by screwing the center rod h into position; then, the drain I is unscrewed and the filling plug m. Through the filling opening of the filter, liquid is introduced again, which filling the container goes through cartridge e and moves upward into the center rod h, pushing ahead of it the air contained in the filter. The air thus expelled moves toward the hydraulic seal of chamber and unable to enter the delivery pipeline, escapes through drain Z, filling thus the total capacity of the filter with the liquid combustible. When this capacity has been entirely filled with liquid combustible, it sumces to simply screw in again the drain Z and the filling plug m, to be able to put the equipment into operation again.

It is understood that during the disassembly of the filter required for cleaning and the replacement of the inside cartridge, no infiltration of air can ever occur in the combustible delivery pipeline, and therefore, after the filter is assembled again and properly filled as indicated above, the unit can immediately again be put into operation without any difliculty.

It goes without saying that the details for carrylng out the invention described above are to be considered only as examples and do not limit the invention, as the latter is susceptible of being modified.

I claim:

1. In. a liquid filter, a head having an inlet opening and an outlet opening, a depending container removably secured to said head into and through which liquid must pass in flowing from the inlet opening to the outlet opening, said head having a chamber of substantial depth for con- 4 taining liquid from which chamber said outlet opening leads at a point substantially below an inlet opening into said chamber, said chamber being of sufficient depth and said point being sufficiently below to maintain a liquid seal when said container is removed from the head.

2. A liquid filter as in claim 1 wherein said chamber is supplied by a center conduit extending from said container to said chamber.

3. In a liquid filter as in claim 1 wherein valve means is located in said head to relieve air trapped in said head.

AUGUSTE GUIOT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

